Recently, the multiplexing of a rank information (RI) feedback report with a wideband channel quality information/precoding matrix index (WB CQI/PMI) feedback report on a physical uplink control channel (PUCCH) has been proposed. One proposed method of multiplexing the RI report with the WB CQI/PMI report on a PUCCH involves allowing different offsets between the RI and the WB CQI/PMI reports while keeping the period of the RI report as an integer multiple of the WB CQI/PMI report. This method would drop the WB CQI/PMI report if a collision occurs between the WB CQI/PMI and RI reports, and the most recently transmitted RI report on the PUCCH would be used by a user equipment (UE) (or subscriber station) to calculate the WB CQI/PMI reported on the configured resource on the PUCCH.
In this method, a Node-B (or base station) configures a single CQI reporting resource for either a RI report or a WB CQI/PMI report for each UE during each reporting instance. A reporting instance refers to a sub-frame where a report is performed. This method does not transmit the RI report and the WB CQI/PMI in the same reporting instance. Rather, only the RI is reported instead of the WB CQI/PMI in every M-th CQI reporting instance according to a higher layer configuration, and the WB CQI/PMI is reported in the remaining CQI reporting instances.
FIG. 3 illustrates an example of CQI reporting instances 300. In this example, M=4 and the offset between the RI report and the WB CQI/PMI is −1. Accordingly, WB CQI/PMI reports 302 occur in reporting instances 1-3 and 5-7 with RI reports 304 occurring in reporting instances 0 and 4 or every 4th (or M-th) reporting instance.
Another proposed method configures the periods of and the offset between the RI and the WB CQI/PMI reports independently. This method also would drop the WB CQI/PMI report if a collision occurs between the WB CQI/PMI report and the RI report.
Similar methods may be used for multiplexing frequency-selective (FS) CQI/PMI and RI reports on a PUCCH.
Therefore, there is a need in the art for an improved system and method for multiplexing WB CQI/PMI, FS CQI/PMI and RI reports on a PUCCH. In particular, there is a need for a comprehensive solution for multiplexing WB CQI/PMI reports with FS CQI/PMI reports as well as RI reports on a PUCCH.